There is a known technique to measure distances to a measuring object (a subject) by using images with different viewpoints. For example, a distance calculation method that uses a technique called “stereo matching” has been suggested (see Patent Document 1, for example).
With the stereo matching technique, depth data that indicates a distance to a subject in a multiview image is calculated from the multiview image formed with images having different viewpoints from one another. With the depth data, multiview images are superimposed on one another to generate an image to be provided to a user.